Special weather phenomenon appeared for the first time in North Korea. What is special weather?

The first abnormal meteorological phenomenon in North Korea refers to the extreme weather phenomenon that occurred in parts of land and sea in western North Korea from the early morning of February 7, 2002 1 year to the early morning of February 9, 20021year. Specific phenomena include: the surface temperature drops to MINUS 2-3 degrees Celsius, while the atmospheric temperature of 1000 hectopascals rises to above zero 2-3 degrees Celsius. Generally speaking, the temperature decreases with the elevation, and the surface temperature is higher than the atmospheric temperature. The weather phenomenon in North Korea this time exceeded 48 hours, and the atmospheric inversion occurred continuously. The humidity of superimposed air increases, and a large-scale and long-term dense fog phenomenon appears.

I. The concept of special meteorology

Special weather phenomenon is a summary of this special weather phenomenon by North Korean news media. In fact, it is what we often call extreme weather. Extreme weather refers to a rare meteorological event in history, with low probability and wide influence. Fog is common all year round, but the fog with long-term inversion in the atmosphere is rare. The types of fog are radiation fog, advection fog, terrain fog, etc. Radiation fog is a kind of small water droplets generated by condensation of water vapor due to low surface temperature and high atmospheric temperature caused by radiation cooling of the surface. But this usually happens in the early morning. As the sun rises and the ground temperature rises, the fog will dissipate. Advection fog often appears in spring and summer, usually in coastal areas. The reason is that with the movement of atmospheric circulation, the warm air mass passes through the cold ground and produces water vapor condensation. This kind of fog can appear at any time of the day, and the duration varies from several hours to several days.

Second, the causes of this special meteorological phenomenon

The abnormal weather in North Korea shows the characteristics of atmospheric inversion of radiation fog and long duration of advection fog. The formation reason is probably due to the special terrain, which leads to the simultaneous formation of advection fog and radiation fog, breeze, low temperature, high humidity, dense fog and other phenomena.